What This Calculator Measures
Estimate compost yield using bin volume, shrink rate, and cycles per year.
By combining practical inputs into a structured model, this calculator helps you move from vague estimation to clear planning actions you can execute consistently.
This calculator estimates compost yield and coverage across cycles.
How to Use This Well
- Enter bin volume and fill percent.
- Set shrink percent and cycles.
- Add density and garden use.
- Review yearly yield.
- Adjust bins if needed.
Formula Breakdown
Yield = volume x fill x (1 - shrink)Yearly: per cycle x cycles.
Mass: volume x density.
Coverage: yearly / use.
Worked Example
- 300 L bin at 85% fill.
- 50% shrink leaves 128 L.
- About 64 kg per cycle.
Interpretation Guide
| Range | Meaning | Action |
|---|---|---|
| Above 100% | Excess. | Share compost. |
| 70-100% | Strong. | Great coverage. |
| 40-70% | Partial. | Add a bin. |
| Below 40% | Low. | Increase cycles. |
Optimization Playbook
- Increase fill: improve yield.
- Add a bin: raise coverage.
- Speed cycles: turn compost more often.
- Track use: align with garden needs.
Scenario Planning
- Baseline: current cycles.
- More cycles: add one cycle.
- Higher shrink: increase by 10%.
- Decision rule: keep coverage above 70%.
Common Mistakes to Avoid
- Overestimating fill percent.
- Ignoring shrink rates.
- Skipping density conversion.
- Using outdated garden use.
Implementation Checklist
- Measure bin volume.
- Estimate shrink rate.
- Track cycles.
- Review yearly yield.
Measurement Notes
Treat this calculator as a directional planning instrument. Output quality improves when your inputs are anchored to recent real data instead of one-off assumptions.
Run multiple scenarios, document what changed, and keep the decision tied to trends, not a single result snapshot.
FAQ
What is typical shrinkage?
40-60% shrink is common.
Does density vary?
Yes, denser compost weighs more.
Can I run more cycles?
Yes, active composting can speed cycles.